Process for breaking petroleum emulsions



Ho Drawing.

'vm DE GROOTE, OF ST. LOUIS, AND ARTHUR Is". TEL, 01 WEBSTER GROVES,

SSOUBI, ASSIGNORS T0 TRETOLI'IE CO, 0F S'IEB VES,

: URI,

PROCESS FOR BREAKING PETROLEUM LSIONS This invention relates to the treatment of emulsions of mineral oil and water, such as petroleum emulsions, for the purpose of separating the oil from the water.

Petroleum emulsions are of the water-inoil type, and comprise fine droplets of naturally-occurring waters or brines, dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion. They are obtained from producing wells and from the bottom of oil storage tanks, and are commonly referred to as cut oil, roily oil, emulsified oil and bottom settlings.

The object of our invention is to provide a novel and inexpensive process for separating emulsions of the character referred to into their component parts of oil and water or brine.

Briefly described, our process consists in subjecting a petroleum emulsion of the water-in-oil type to the action of a treating agent or demulsifying agent of the kind hereinafter described, thereby causing the emulsion to break down 'and separate into its component parts of oil and water or brine, when the emulsion is permitted to remain in a quiescent state after treatment.

The treating agent or demulsifying agent used in our process consists of a sulfoabietene acid body or a mixture that contains a sulfo-abietene acid body.

Abietene is derived from abietic acid. Abietic acid is obtained from wood rosin or colophony. Natural rosin is a solid vitreous modification of abietic acid. Various methods and procedures are employed to obtain abietic acid from rosin, and abietic acid can be treated in various ways so as to yield or produce abietene. In producing abietene commercially it is not necessary to convert rosin or like material into abietic acid and then convert the abietic acid into abietene, but as a matter of fact, abietene may be obtained directly from wood rosin by thermal decomposition. Such abietene of commerce is in a relatively pure state and contains only a proximately one percent of abietic acid.

hemically, it is probable that abietene is decahydroretene.

Application filed march 25, 1932. Serial in. 601,294.

A treating agent suitable for use in our process may be obtained by sulfonating abietene at a relatively low temperature by the use of a relatively strong sulfonating agent, such as 100% sulfuric acid. The product of the above reaction may be properly termed a sulfonic acid, although it is possible that under certain conditions it may be more akin to an acid sulfate than to a true sulfonic acid. The analogy may be somewhat similar to the reaction of propylene and sulfuric acid, in which propyl hydrogen sulfate is obtained, or even somewhat similar to a reaction in which dialkyl sulfate is formed. At times more than one sulfo group may be introduced. We consider a product or a material of the kind above referred to, when in the acid state, or after neutralization with a base, or after esterification, as coming within the term suliEo-abietene acid body, as herein used. The exact composition of said product or material is unimportant, so far as its industrial application in the present process is concerned, and we are employing the term sulfo-abietene acids to indicate materials obtained from abietene b means of strong su-lfonating agents, inclu ing oleum and chlorosulfonic acid, without differentiating as to whether they are true sulfonic acids or acid sulfates, or of allied structure. The arm sulo-abietene acid body is herein used in a generic sense to mean a sulfo-abietene compound of the kind previously described, in the form of an acid, or a salt or an esterthat is, the acid hydrogen may be present as such or replaced by an equivalent. The above men-r and stirring continued for twent -four hours; The sulfonated mass is then di uted so that the. finalconcentration of sulfuric acid is isting conditions. It can be used insubstanapproximately 38 to 42 percent, and it is allowed to'stand until the u per layer, consisting of a dark, oily aci ic mass, shows a clear line of separation. We will refer to this specific material produced by the above reaction or'proc'edure as ,abietene sulfonic acid.

The said dark, oily, acidic mass (abietene sufonic acid) is either'used as such to constitute the treating agent of our process, or it'may be neutralized prior to use, with any suitable basic material, such as caustic soda,

caustic potash, sodium carbonate, potassium carbonate, ammonium carbonate, ammonium hydroxide, calcium hydroxide, magnesium carbonate, etc. If desired, abietenesulfonic acid, as above described, or: a sulfo abietene I acid, may be converted into esters by conven 'tional reaction methods with suitable alcohols, aromatic or aliphatic,'and the resulting i ester'or esters used to constitute the treating agent of -ourprocess. Some of the esters tained by neutralization with inorganic bases .are usually water-soluble, and a few may even be water-insoluble, as in the case of aluminum. I

The specific form, state or condition of the treating agent at the time it is used or ap plied to the petroleum emulsion to be treated is immaterial and may be varied to suit ex tially anhydrous state or in solutions of any convenient stren h. A concentrated solution of abietene sul onic acid can be emulsified with oil by the agency of any suitable oilsoluble emulsifiers, such as calcium ol'eate and the resultant mixture used to constitute the treating agent of our process. The treating agent'can be formed entirely from a material of the kind previously described, or it can be formed from such a material in combination with another or other well knowntreating agents for petroleum emulsions of the waterin-oil type, such as water softeners, modified fatty bodies, or their salts, petroleum sulfonic acids or their salts, or other substances known to have similar demulsifying properties.

In practising our process, a treating agent or demulsifying agent of the kind above described may be brought in contact with the emulsion to be treated in any of the numerous ways now employed in the treatment of petroleum emulsions of the water-in-oil type with chemical demulsifying agents, such, for example, as by introducing the treating agent into the well in which the emulsion is produced, introducing the treating agent into a conduit through which the emulsion is flowing, introducing the treating agent into a tank in which the emulsion is stored, or in-,

troducing the treating agent into a container that holds asludge obtained from the bottomof an oil storage tank. In some intreating agent into a producing well in such a way that'it'will become-mixed with water. and oil that are emerging from the surround- 'ing strata, before said water and oil enter the barrel of the well pump or thetu-bing up-through which said water and oil flow to the surface of the ground. After treat ment the emulsion is allowed to'stand in a quiescent state,'usually in a settling tank, at a temperature ivarying from. atmospheric temperature to about 200 F., so as'to permit the water or brine to separate fromthe oil, it being preferable to keep the. temperature low enough so as to prevent the valuable con s'tituents of the oilfrom volatilizing. If desired, the treated 'emulsio'n may be acted upon by' one or the other of various kinds of a pparatusnow used in the operation of breaking petroleum emulsions, such'as'ho- 'mogemzers, hay tanks, gun barrels, filters, centrifuges, or electrical dehydrators.

The amount of treating agent on'the anhydrous basis that is required to break-the emulsion may vary from'aproximately 1 part of treating agent to 500 arts of emulsion,

20,000 parts of emulsion, depending upon the type or kind of emulsion being treated.

In treating exceptionallyrefractoryemul sions ofthe kind commonly referred to as" tank bottoms or residual pit oils, the minimum ratio above referred to is often necessary, but in treating fresh emulsions, i. e., emulsions that will yield readily to the action of chemical demulsifying agents, the maximum ratio above mentioned will frequently produce highly satisfactory results. For the average petroleum emulsion of the water-in-oil type a ratio of 1 part of treating agent to 5000 parts of emulsion will usually be found to produce commercially satisfac- 3. A. process for breaking petroleum emulsions of the water-in-oil type, which consists-in subjecting the emulsion to the acup to a ratio of 1 part o treating agent to stances, it may be advisable to introduce-the 7- f emme tion of a demulsifying ent containing a, water-soluble salt of a S1181? -abietene acid,

4;. A process for breaking petroleum emulsions of the water-in-oil type, which 5 consists in subjecting the emulsion to the action of a demulsifying agent containing the sodium salt of a sulfo-abietene acid.

5. A. process for breaking petroleum emulsions of the water-in-oil type, which 1 consists in subjecting the emulsion to the action of a demulsifying agent containing the sodium salt of abietene sulfonic acid, as herein defined.

MELVIN DE GROOTE.- ARTHUR F. WIRTEL. 

